SU-E-T-147: Scintillating Fiber Array to Determine the Proton Beam Range

Abstract

Purpose: To develop the scintillating fiber array dosimeter to determine the proton beam range for the purpose of quality assurance of the patient in the proton therapy. Methods: A scintillating fiber dosimeter was composed of a commercial scintillating fiber optically coupled with organic based optical fiber. An array of scintillating fibers was settled inside a water bath. The scintillating light was amplified by photo multiplier tube before being gathered by commercial data acquisition system. Bragg peak and SOBP was measured with scintillating fiber dosimetry. The correction of the signal between the dosimeters and quenching effect of each dosimeter itself were conducted in home-made software. The results were compared with the ion chamber.Results: The signals from each scintillating fiber dosimeter showed randomly distributed along the depth. After calibrating between the dosimeters, the signals showed similar curve to Bragg peak and SOBP. Then correcting the quenching effect made the signal to coincident with the icon chamber results Conclusions: We improved the scintillating fiber optic dosimetry system which is previously developed in scanning type to the array type. The developed dosimetry system can provided more applicable and faster way to determine the proton beam range.